Electromagnetic relay



Jan. 22, 1946.

J. H. HORMAN ELECTROMAGNETIC RELAY Filed July '31, 1943 2 Sheets-Sheet -1 INVENTOR A i ToRwsv Jan. '22, 1946.

Filed July 31 1943 .J. H. HO RMAN I ELECTROMAGNETIC RELAY 2 Sheets-Sheet 2 INVENTOR ATTORNZS Patented Jan. 22, 1946 ELECTROMAGNETIC RELAY John H. Human, Tuckahoe, N. Y., assignor, by

. mesne assignments, to Allied Control Com-r pany, Inc., NewYork, N. Y., a cor'poration of New York Application July 31, 1943, Serial No. 426,849 2 Claims. (Cl. 200-164 1 This invention relates to electromagnetic reays.

An object of this invention is an electromagnetic relay of such construction that the effect of vibration of the relay on the armature is reduced to a minimum.

Another object of the invention is an electromagnetic relay having an arrangement of the coil and armature by which the electromagnetic force developed by the coil is converted into maximum pull on the armature.

A still further object of the invention is an electromagnetic relay equipped with a make-andbreak arrangement for the controlled circuits in which friction is minimized and good contact is aissured even under conditions of severe vibrat on.

Other objects, novel features and advantages of this invention will become apparent from the following specification and accompanying drawings, wherein:

Fig. 1 is a side elevation of a relay embodying the invention;

Fig. 2 is a plan view thereof; Fig. 3 is a section on the line 3-3 of Fig. 1; Fig. 4 is a section on the line 4-;4 of Fig. l, and

Fig. 5 is a perspective view of a detail.

The base of the relay consists of two plates it and i composed of magnetic metal and a pair of .mounting studs l2 are attached to the plate collar 22 of greater diameter than the portion of the shaft extending through the plate 20 so as to prevent upward movement of the shaft. The shaft supports an armature 23 which is symmetrical with respect to the shaft. The armature includes two wings, each of which is provided with an arcuate recess 24 properly shapedpartially to enclose the projecting end of one of the cores l5 and it when the armature is in the position shown in dotted lines in Fig. 4. The armature 23 may be conveniently described as being substantially S-shape. The plate is is provided with a stop 25 for engagement by one wing of the armature to limit counter-clockwise movement of the armature as shown in Fig. 4, clockwise movement of the armature being limited by the cores l3 and I4. Springs 26 bias-the armature into engagement with a stop 25 in which position the wings of the armature are spaced from the cores l3 and M.

A plate 21 of insulating material rests on the non-magnetic plate 2|! and screws 28 pass through both plates and are threaded into the cores l3 and M to attach the plates to the cores. The plate 21 has a bore through which the shaft 2| extends beyond the top surface of the plate.'

A block 28 of insulating material is attached to the shaft 2| by a bolt 28. Apair of contact mem- It. A pair of rods I3 and ll of .magnetic'metal have extensions I5 and I8 of smaller diameter than the remainder extending through the plates l0 and II and serving to hold said plates together as well as to attach the rods l3 and H to the relay base. Field coils l1 and I8 surround the rods I3 and I4 and combine therewith to bers 30 are attached to the block 28. Each of these contact members is composed of a thin plate of electrically-conductive metal bent into U-shape with the ends of the member contacting the under and upper surfaces of the block form electro-magnets of which the rods l3 and I4 constitute the cores. The cores l3 and H are of greater length than the coils l1 and 18 so that they project beyond the ends of the coils.

A plate I! of non-magnetic metal rests on the ends of the coils l1 and I8 and is provided with apertures through which pass the projecting ends of the cores l3 and II. A plate 28, also of nonmagnetic metal, rests on the ends of the pole pieces l3 and I in which position it is held by means subsequently to be described. -A shaft 2| is joumalled in apertures in the plates l9 and 20 between and parallel to the core axes. The portion of the shaft 2| projecting through the plate I! is of less diameter than the armature-s to form a shoulder limiting downward movement and being attached thereto by any suitable means, such as rivets. Each leg of the U member is of greater width than the bight thereof and is provided with a plurality of slits to form fingers 3|. Theflngers 3| are bowed inwardly so that the effective width of the contact member is less at its edges than at its central portion.

At each end of the plate 21 is mounted a contact'32 having a flat central portion 33 leading to a binding post 34 and .two oblique wing portions 35 diverging upwardly from the portion 33. Also, at each end of the plate 21 are mounted two contacts 36, each of which has an arm 31 projecting inwardly over a wing 35 with its end slightly upturned to produce a tapering gap with the wing 85 and provided with a binding post 88. The arrangement of the contacts just described 1 is such that fingers 3| of the contact member 38 are adapted to enter thegaps upon rotation of the shaft 2|. Also provided 'on the plate 21 of the shaft and the shaft also is equipped with a so are 'binding posts 33 attachedto wires 40 leading to the coils II and I8 and providing means for supplying energizing current to the coils.

The operation of the above-described relay is as follows: When the coils I! and i8 are deenergized, the springs 25 maintain the armature 23 and shaft 2| in the position shown in full lines in Fig. 4. with such arrangement of the armature and shaft, the block 28 and contacts 30 are in the position shown in full lines in Fig. 2 with each contact 30 bridging one gap between contacts 32 and 36 at each end oi the plate 21 as shown in Fig. 3 with the other gap -open. Energization of the coils H and it produces an electromagnetic force which attracts the armature into the position shown in dotted lines in Fig. 4, thereupon rotating the block 28 clockwise from the position shown in Fig. 2 to open-circuit the contacts originally closed and to close-circuit the contacts originally open. By reason of the shape oi the fingers 3|, they develop a spring pressure tending to assist in the clockwise movement of the armature out of the gap and also to reduce to a minimum the friction developed upon the contact entering the opposite gap. The provision of several fingers 3| insures firm engagement between the movable contact and the fixed contacts should there be any irregularity or outof-alinement condition in the contacts. In addition, the provision of the rotary armature reduces to a minimum the eifect thereon or vibration of the relay.

I claim:

1. In a switch, a pair of stationary contacts arranged in spaced relation to define a gap, a third contact, rotatable means for supporting said third contact for movement into and out of simultaneous engagement with both said stationary contacts, said third contact consisting of a U-shaped member having the ends or the legs thereof attached to said supporting means and having wider portions with corresponding edges thereof engageable with said stationary contacts, the spacing of said portions along said edges being less than the width of said gap and increasing to a greater width than said gap.

2. In a switch, a pair-of stationary contacts arranged in spaced relation to define a gap, 3, third contact, rotatable means for supporting said third contact for movement into and out of simultaneous engagement with both said stationary contacts, said third contact consisting of a U-shaped member having the ends of the legs thereof attached to said supporting means and having wider portions with corresponding edges thereof engageable with said stationary contacts, the spacing of said portions along said edges being less than the width of said gap and increasing to a greater width than said gap, and slits in said legs extending to said edges thereof in the direction of movement of said member into engagement with said stationary contacts whereby the effective spacing of said edges may be reduced.

J JOHN H. HORMAN. 

